<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    /* where选择器权重为0，只要被where选择器包裹 权重就为0 */
    p {
      color: green;
    }
    /* 权重为1，和上面那位是一样的，只是层叠性 */
    :where(.box) p {
      color: red;
    }
  </style>
</head>
<body>
  <div class="box">
    <p>我是p标签</p>
  </div>
</body>
</html>